#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#pragma GCC optimize("O3,unroll-loops")
#include <bits/stdc++.h>
#define all(v) v.begin(), v.end()
#define pb push_back
#define ss second
#define ff first
#define vt vector
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
const int inf = 1e9;
const int mod = 1e9+7;
const int maxn = 1e5 + 1;
vt<int> g[maxn];
vt<pii> hv[maxn];
bool was[maxn];
int dp[maxn];
void solve() {
int n, m, q, sq;
cin >> n >> m >> q;
sq = sqrt(n);
if(sq * sq != n)sq++;
for(int i = 0, u, v; i < m; i++){
cin >> u >> v;
g[--v].pb(--u);
}
for(int i = 0; i < n; i++){
hv[i].pb({0, i});
for(auto k : g[i]){
vt<pii> res;
int j = hv[i].size() - 1, o = hv[k].size() - 1, sz = 0;
while((j >= 0 || o >= 0) && sz < sq){
while(j >= 0 && was[hv[i][j].ss])j--;
while(o >= 0 && was[hv[k][o].ss])o--;
if(j < 0 && o < 0)break;
if(o < 0)res.pb(hv[i][j--]);
else if(j < 0)res.pb({hv[k][o].ff + 1, hv[k][o].ss});
else if(hv[i][j].ff > hv[k][o].ff + 1)res.pb(hv[i][j--]);
else res.pb({hv[k][o].ff + 1, hv[k][o].ss});
was[res.back().ss] = 1;
sz++;
}
for(auto j : res)was[j.ss] = 0;
reverse(all(res));
hv[i] = res;
}
}
for(int i = 0; i < q; i++){
int k, t;
cin >> t >> k;
--t;
vt<int> x(k);
for(int j = 0; j < k; j++){
cin >> x[j];
was[--x[j]] = 1;
}
if(k > sq){
for(int j = 0; j < n; j++){
if(was[j])dp[j] = -inf;
else dp[j] = 0;
for(auto o : g[j]){
dp[j] = max(dp[j], dp[o] + 1);
}
}
if(dp[t] < 0)cout << "-1\n";
else cout << dp[t] << '\n';
}
else {
int sz = hv[t].size() - 1;
while(sz >= 0 && was[hv[t][sz].ss]){
sz--;
}
if(sz < 0)cout << "-1\n";
else cout << hv[t][sz].ff << '\n';
}
for(auto j : x)was[j] = 0;
}
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
int times = 1;
//cin >> times;
for(int i = 1; i <= times; i++) {
solve();
}
return 0;
}
